* {
    user-select: none;
    -ms-user-select: none;
    outline: 0;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}

body {
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: rgb(25, 39, 44);
    font-family: consolas;
}

a {
    position: relative;
    display: inline-block;
    padding: 15px 30px;
    color: skyblue;
    text-transform: uppercase;
    letter-spacing: 4px;
    text-decoration: none;
    font-size: 24px;
    overflow: hidden;
    transition: 0.2s;
}

a:hover {
    color: #11538c;
    background: skyblue;
    box-shadow: 0 0 10px skyblue,
                0 0 20px skyblue,
                0 0 30px skyblue,
                0 0 40px skyblue;
    transition-delay: 0.8s;
}

a span {
    position: absolute;
    display: block;
}

a span:nth-child(1) {
    top: 0;
    left: -100%;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, transparent, skyblue);
}

a:hover span:nth-child(1) {
    top: 0;
    left: 0;
    background: linear-gradient(90deg, transparent, skyblue);
    transition: 0.8s;
}


a span:nth-child(2) {
    top: -100%;
    right: 0;
    width: 2px;
    height: 100%;
    background: linear-gradient(180deg, transparent, skyblue);
}

a:hover span:nth-child(2) {
    top: 0;
    background: linear-gradient(180deg, transparent, skyblue);
    transition: 0.8s;
    transition-delay: 0.2s;
}


a span:nth-child(3) {
    bottom: 0;
    right: -100%;
    width: 100%;
    height: 2px;
    background: linear-gradient(270deg, transparent, skyblue);
}

a:hover span:nth-child(3) {
    bottom: 0;
    right: 0;
    background: linear-gradient(270deg, transparent, skyblue);
    transition: 0.8s;
    transition-delay: 0.4s;
}


a span:nth-child(4) {
    left: 0;
    bottom: -100%;
    width: 2px;
    height: 100%;
    background: linear-gradient(0deg, transparent, skyblue);
}

a:hover span:nth-child(4) {
    left: 0;
    bottom: 0;
    background: linear-gradient(0deg, transparent, skyblue);
    transition: 0.8s;
    transition-delay: 0.6s;
}